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Related papers: Probing the structure and evolution of active gala…

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Understanding the composition and structure of the broad-line region (BLR) of active galactic nuclei (AGN) is important for answering many outstanding questions in supermassive black hole evolution, galaxy evolution, and ionization of the…

Astrophysics of Galaxies · Physics 2015-06-22 Joshua Moloney , J. Michael Shull

Continuum polarization over the UV-to-microwave range is due to dichroic extinction (or emission) by asymmetric, aligned dust grains. Because of both grain alignment and scattering physics, the wavelength dependence of the polarization,…

Pollux is a project of UV spectropolarimeter proposed as a European contribution for the planned NASA-led Habitable Worlds Observatory. In the present study we consider design options for four spectral channels. The two main channels…

Instrumentation and Methods for Astrophysics · Physics 2024-10-03 Eduard Muslimov , Coralie Neiner , Jean-Claude Bouret

Short millimeter observations of radio-loud AGN offer the opportunity to study the physics of their inner relativistic jets, from where the bulk millimeter emission is radiated. Millimeter jets are significantly less affected by Faraday…

Astrophysics of Galaxies · Physics 2014-07-02 I. Agudo , C. Thum , J. L. Gomez , H. Wiesemeyer

Over its 13 years of operation (1990 -- 2002), the Faint Object Camera (FOC) on board the Hubble Space Telescope (HST) observed 26 individual active galactic nuclei (AGNs) in ultraviolet (UV) imaging polarimetry. However, not all of the…

Astrophysics of Galaxies · Physics 2023-10-18 Thibault Barnouin , Frédéric Marin , Enrique Lopez-Rodriguez , Léo Huber , Makoto Kishimoto

The anisotropic nature of active galactic nuclei (AGN) is thought to be responsible for the observational differences between type-1 (pole-on) and type-2 (edge-on) nearby Seyfert-like galaxies. In this picture, the detection of emission…

Astrophysics of Galaxies · Physics 2014-04-10 F. Marin

We present a 5-8 micron analysis of the Spitzer-IRS spectra of 71 ultraluminous infrared galaxies (ULIRGs) with redshift z < 0.15, devoted to the study of the role of active galactic nuclei (AGN) and starbursts (SB) as the power source of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 E. Nardini , G. Risaliti , M. Salvati , E. Sani , Y. Watabe , A. Marconi , R. Maiolino

We present new results for a sample of 33 narrow-lined UV-selected active galactic nuclei (AGNs), identified in the course of a spectroscopic survey for star-forming galaxies at z ~ 2-3. The rest-frame UV composite spectrum for our AGN…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Kevin N. Hainline , Alice E. Shapley , Jenny E. Greene , Charles C. Steidel

The ionizing fluxes from quasars and other active galactic nuclei (AGN) are critical for interpreting the emission-line spectra of AGN and for photoionization and heating of the intergalactic medium. Using ultraviolet spectra from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 J. Michael Shull , Matthew Stevans , Charles W. Danforth

Active Galactic Nuclei (AGN) with bright radio jets offer the opportunity to study the structure of and physical conditions in relativistic outflows. For such studies, multi-frequency polarimetric very long baseline interferometric (VLBI)…

Astrophysics of Galaxies · Physics 2015-11-27 Jae-Young Kim , Sascha Trippe , Bong Won Sohn , Junghwan Oh , Jong-Ho Park , Sang-Sung Lee , Taeseok Lee , Daewon Kim

Observing programs comprising multiple scientific objectives will enhance the productivity of NASA's next UV/Visible mission. Studying active galactic nuclei (AGN) is intrinsically important for understanding how black holes accrete matter,…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-17 Gerard Kriss , Nahum Arav , Anton Koekemoer , Smita Mathur , Bradley M. Peterson , Jennifer E. Scott

Low-Luminosity Active Galactic Nuclei (LLAGN) provides a unique view of Comptonization and non-thermal emission from accreting black holes in the low-accretion rate regime. However, to decipher the exact nature of the Comptonizing corona in…

Objective-prism surveys for UV-excess and emission-line objects, especially the First and Second Byurakan Surveys, have been central to the study of active galactic nuclei (AGNs). We review previous line-selected surveys for AGNs and…

Astrophysics · Physics 2007-05-23 Caryl Gronwall , Vicki Sarajedini , John Salzer

Active galactic nuclei (AGN) produce the highest intrinsic luminosities in the Universe from within a compact region. The central engine is thought to be powered by accretion onto a supermassive black hole. A fraction of this huge release…

Astrophysics of Galaxies · Physics 2018-05-07 Beatriz Agís González , Damien Hutsemékers , Giovanni Miniutti

Over three decades of reverberation mapping (RM) studies on local broad-line active galactic nuclei (AGNs) have measured reliable black-hole (BH) masses for $> 100$ AGNs. These RM measurements reveal a significant correlation between the…

The Faint Object Camera (FOC) on board the Hubble Space Telescope (HST) acquired high-resolution spatially resolved polarimetric images of nearby active galactic nuclei (AGNs) in the near-ultraviolet (near-UV) band. Eight of the 25…

Astrophysics of Galaxies · Physics 2025-10-15 Thibault Barnouin , Frédéric Marin , Enrique Lopez-Rodriguez

Active Galactic Nuclei emit over the entire electromagnetic spectrum with the peak of the accretion disk emission in the far-UV, a wavelength range historically difficult to investigate. We use here the GALEX (Galaxy Evolution Explorer)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Elena Marchese , R. Della Ceca , A. Caccianiga , A. Corral , P. Severgnini

We have obtained new spectropolarimetric observations at visible wavelengths of the changing-look active galactic nucleus (AGN) Mrk 1018. The AGN direct spectrum shows an extremely weak continuum with faint broad H$\beta$ and H$\alpha$…

Astrophysics of Galaxies · Physics 2021-01-04 Damien Hutsemékers , Beatriz Agís González , Frédéric Marin , Dominique Sluse

We present preliminary results of JVLA wideband full polarization observations of a sample of Active Galactic Nuclei (AGN) with very high Rotation Measure (RM) values, a sign of extreme environment. Polarization properties show a complex…

We use a complete sample of Lya emission-line selected AGNs obtained from nine deep blank fields observed with the grism spectrographs on the Galaxy Evolution Explorer (GALEX) satellite to measure the normalization and spectral shape of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 A. J. Barger , L. L. Cowie